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Background: Atypical ductal hyperplasia (ADH) is a benign epithelial proliferative lesion with histologic features resembling those seen in low grade ductal carcinoma in situ (DCIS). Surgical excision of the biopsy site is the standard management approach. The objective of this study was to determine the upgrade rate from ADH on stereotactic breast biopsies to DCIS or invasive carcinoma (IC) in our institution. We also sought to identify clinical, pathologic and radiologic predictive factors associated with risk of upgrade., Materials and Methods: Clinical charts, mammograms and pathology reports were reviewed for all women with a stereotactic breast biopsy showing ADH and subsequent surgery at our institution between 2008 and 2018. When available, mammograms were re-reviewed by a radiologist for this study., Results: 295 biopsies were analyzed in 290 patients. Mean age was 56 y old. Upgrade rate was 10.5% of which 7.5% were DCIS and 3.1% IC. Mammograms were reviewed by a radiologist in 161 patients from 2013 to 2018. In this subset of patients, the rate of upgrade was 8.7% (4.35% DCIS and 4.35% IC). A statistically significant difference he largest size of the microcalcification clusters on mammogram was observed between the upgraded and the non-upgraded subgroups (14.2 mm versus 8.9 mm, P = 0.03) CONCLUSIONS: The evaluation of the largest size of microcalcification clusters on mammogram as a cut-off feature could be considered to choose between an observational versus a surgical approach. This large series provides contemporary data to assist informed decision making regarding the treatment of our patients., (Copyright © 2021. Published by Elsevier Inc.)

Protein glycosylation is arguably the paramount post-translational modification on recombinant glycoproteins, and highly cited in the literature for affecting the physiochemical properties and the efficacy of recombinant glycoprotein therapeutics. Glycosylation of human immunoglobulins follows a reasonably well-understood metabolic pathway, which gives rise to a diverse range of asparagine-linked (N-linked), or serine/threonine-linked (O-linked) glycans. In N-linked glycans, fucose levels have been shown to have an inverse relationship with the degree of antibody-dependent cell-mediated cytotoxicity, and high mannose levels have been implicated in potentially increasing immunogenicity and contributing to less favorable pharmacokinetic profiles. Here, we demonstrate a novel approach to potentially reduce the presence of high-mannose species in recombinant human immunoglobulin preparations, as well as facilitate an approximate 100% replacement of fucosylation with arabinosylation in Chinese hamster ovary cell culture through media supplementation with D-arabinose, an uncommonly used mammalian cell culture sugar substrate. The replacement of fucose with arabinose was very effective and practical to implement, since no cell line engineering or cellular adaptation strategies were required. Arabinosylated recombinant IgGs and the accompanying reduction in high mannose glycans, facilitated a reduction in dendritic cell uptake, increased FcγRIIIa signaling, and significantly increased the levels of ADCC. These aforementioned effects were without any adverse changes to various structural or functional attributes of multiple recombinant human antibodies and a bispecific DVD-Ig. Protein arabinosylation represents an expansion of the N-glycan code in mammalian expressed glycoproteins.

Mammalian cells in culture rely on sources of carbohydrates to supply the energy requirements for proliferation. In addition, carbohydrates provide a large source of the carbon supply for supporting various other metabolic activities, including the intermediates involved in the protein glycosylation pathway. Glucose and galactose, in particular, are commonly used sugars in culture media for these purposes. However, there exists a very large repertoire of other sugars in nature, and many that have been chemically synthesized. These sugars are particularly interesting because they can be utilized by cells in culture in distinct ways. In the present work it has been found that many infrequently used sugars, and the corresponding cellular response towards them as substrates, led to differences in the protein N-glycosylation profile of a recombinant glycoprotein. The selective media supplementation of raffinose, trehalose, turanose, palatinose, melezitose, psicose, lactose, lactulose, and mannose were found to be capable of redirecting N-glycan oligosaccharide profiles. Despite this shifting of protein glycosylation, there were no other adverse changes in culture performance, including both cell growth and cellular productivity over a wide range of supplemented sugar concentrations. The approach presented highlights a potential means towards both the targeted shifting of protein glycosylation profiles and ensuring recombinant protein comparability, which up to this point in time has remained under-appreciated for these under-utilized compounds. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:511-522, 2017., (© 2017 American Institute of Chemical Engineers.)

A mixed-methods approach was used to develop a culturally appropriate health intervention over radio within the Inuit community of Pangnirtung, Nunavut (NU), Canada. The radio dramas were developed, recorded and tested pre-intervention through the use of Participatory Process and informed by the extended elaboration likelihood model (EELM) for education-communication. The radio messages were tested in two focus groups (n = 4 and n = 5) to determine fidelity of the radio dramas to the EELM theory. Focus group feedback identified that revisions needed to be made to two characteristics required of educational programmes by the EELM theorem: first, the quality of the production was improved by adding Inuit youth recorded music and second, the homophily (relatability of characters) of radio dramas was improved by re-recording the dramas with voices of local youth who had been trained in media communication studies. These adjustments would not have been implemented had pre-intervention testing of the radio dramas not taken place and could have reduced effectiveness of the overall intervention. Therefore, it is highly recommended that media tools for health communication/education be tested with the intended target audience before commencement of programmes. Participatory Process was identified to be a powerful tool in the development and sustainability of culturally appropriate community health programming., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

With the advent of new initiatives to develop chemically defined media, cell culture scientists screen many additives to improve cell growth and productivity. However, the introduction or increase of supplements, typically considered beneficial or protective on their own, to the basal media or feed stream may cause unexpected detrimental consequences to product quality. For instance, because cultured cells are constantly under oxidative stress, ascorbic acid (vitamin C, a potent natural reducing agent) is a common additive to cell culture media. However, as reported herein, a recombinant monoclonal antibody (adalimumab) in cell culture was covalently modified by xylosone (molecular weight 148), an oxidative product of ascorbate. Containing reactive carbonyl groups, xylosone modifies various amines (e.g., the N-termini of the heavy and light chains and susceptible lysines), forming either hemiaminal (+148 Da) or Schiff base (imine, +130 Da) products. Our findings show, for the first time, that ascorbate-derived xylosone can contribute to an increase in molecular heterogeneity, such as acidic species. Our work serves as a reminder that additives to cell culture and their metabolites may become reactive and negatively impact the overall product quality and should be carefully monitored with any changes in cell culture conditions.

Charge variants in recombinant proteins are an important series of protein modifications, whose potential role on protein stability, activity, immunogenicity, and pharmacokinetics continues to be studied. Monoclonal antibodies in particular have been shown to have a wide range of acidic species variants, including those associated with the addition of covalent modifications as well as the chemical degradation at specific peptide regions on the antibody. These variants play a significant role toward the overall heterogeneity of recombinant therapeutic proteins and are typically monitored during manufacturing to ensure they lie within proven acceptable ranges. In this work, it has been found that the supplementation of members of the bioflavonoid chemical family into mammalian cell culture media was effective toward the reduction of acidic species charge variants on recombinant monoclonal antibodies and dual variable domain immunoglobulins. The demonstrated reduction in acidic species through the use of bioflavonoids facilitates the manufacturing of a less heterogeneous product with potential improvements in antibody structure and function., (© 2015 American Institute of Chemical Engineers.)

Protein glycosylation is an important post-translational modification toward the structure and function of recombinant therapeutics. The addition of oligosaccharides to recombinant proteins has been shown to greatly influence the overall physiochemical attributes of many proteins. It is for this reason that protein glycosylation is monitored by the developer of a recombinant protein therapeutic, and why protein glycosylation is typically considered a critical quality attribute. In this work, we highlight a systematic study toward the supplementation of sucrose and tagatose into cell culture media for the targeted modulation of protein glycosylation profiles on recombinant proteins. Both sugars were found to affect oligosaccharide maturation resulting in an increase in the percentage of high mannose N-glycan species, as well as a concomitant reduction in fucosylation. The latter effect was demonstrated to increase antibody-dependent cell-mediated cytotoxicity for a recombinant antibody. These aforementioned results were found to be reproducible at different scales, and across different Chinese hamster ovary cell lines. Through the selective supplementation of these described sugars, the targeted modulation of protein glycosylation profiles is demonstrated, as well as yet another tool in the cell culture toolbox for ensuring product comparability., (© 2014 American Institute of Chemical Engineers.)

The HIV infection of a family member can impact family quality of life (FQoL). The objectives of this study are to (1) describe patterns of FQoL among mothers living with HIV (MLHIV) and (2) identify key factors associated with FQoL in families affected by HIV. Recruitment took place in HIV-specialized clinics and community organizations. A 100 MLHIV and 67 of their children participated in this study. Mothers were on average 40.8 years old and reported having an average of two dependent children at home (M = 2.1, SD = 1.0). Participating children were 16.2 years old, on average. Half of the children were boys (50.8%). More than half were aware of their mother's positive HIV status (68.2%) and 19.7% were diagnosed with HIV. All HIV-positive children were aware of their status. A latent profile analysis was performed on the five continuous indicators of FQoL, and three main profiles of self-reported FQoL among MLHIV were established: high FQoL (33%), moderate FQoL (58%), and low FQoL (9%). Among the mothers' characteristics, education, physical functioning, social support, and resilience increased FQoL, while anxiety and irritability decreased FQoL. Among the children's characteristics, resilience followed the FQoL profile. A trend was observed toward children's greater awareness of the mother's HIV status in high and low FQoL profiles. Additionally, irritability tended to be higher within the lower FQoL profile. FQoL profiles can be used to identify families needing special care, particularly for family interventions with both parents and children. Other relevant indicators must be studied (e.g., closeness and support between family members, availability and accessibility of care, family structure, father-child relationships, and medical condition of the mother) and longitudinal research conducted to estimate the direction of causality between FQoL profile and individual family member characteristics.

The design of basal and feed media in mammalian cell culture is paramount towards ensuring acceptable upstream process performance in various operation modes, especially fed-batch culture. Mammalian cell culture media designs have evolved from the classical formulations designed by Eagle and Ham, to today's formulations designed from continuous improvement and statistical frameworks. Feed media is especially important for ensuring robust cell growth, productivity, and ensuring the product quality of recombinant therapeutics are within acceptable ranges. Numerous studies have highlighted the benefit of various media designs, supplements, and feed addition strategies towards the resulting cell culture process. In this work we highlight the use of a top-down level approach towards feed media design enabled by the use of select surfactants for the targeted enrichment of a chemically defined feed media. The use of the enriched media was able to improve product titers at g/L levels, without adversely impacting the growth of multiple Chinese Hamster Ovary cell lines or the product quality of multiple recombinant antibodies., (© 2013 American Institute of Chemical Engineers.)

The critical impairments of innate and adaptive immunity that cause susceptibility to mucosal candidiasis in human immunodeficiency virus (HIV) infection have not been fully determined. We therefore conducted an analysis of macrophage-mediated responses to Candida albicans in transgenic (Tg) mice expressing Nef, Env, and Rev of HIV type 1 (HIV-1) in CD4(+) T cells, dendritic cells, and macrophages and developing an AIDS-like disease (CD4C/HIV(MutA) Tg mice). Macrophages were successfully recruited to the oral and gastric mucosae of these Tg mice in response to chronic carriage of C. albicans and displayed polarization toward an alternatively activated phenotype. Functionally, peritoneal macrophages from uninfected Tg mice exhibited increased phagocytosis of C. albicans and enhanced production of interleukin 6 and monocyte chemoattractant protein 1, demonstrating that the HIV-1 transgene independently activates selected macrophage functions. Production of H(2)O(2) by macrophages from Tg mice primed with gamma interferon and treated with phorbol 12-myristate 13-acetate or C. albicans was moderately reduced, but expression of the HIV-1 transgene did not alter production of nitric oxide or reduce killing of C. albicans. A knockout of the inducible nitric oxide synthase (NOS2) gene in these Tg mice did not augment oral or gastrointestinal burdens during chronic carriage of C. albicans or cause systemic dissemination, likely due to a redundancy provided by partially preserved production of H(2)O(2) and oxygen-independent candidacidal mechanisms. Thus, the macrophage response to C. albicans is largely preserved in these Tg mice, and no functional macrophage defect appears to primarily determine the susceptibility to mucosal candidiasis.